Fluid and Electrolyte Balance Flashcards
7 cards from real CRNI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Fluid and Electrolyte Balance flashcards as text
A patient receiving TPN develops confusion, muscle weakness, and a serum phosphate of 1.2 mg/dL. Which condition is most likely?
Answer: Refeeding syndrome
Refeeding syndrome causes severe hypophosphatemia as glucose infusion shifts phosphate intracellularly.
Which IV fluid is most appropriate for initial resuscitation of a patient with severe burns?
Answer: Lactated Ringer's
Lactated Ringer's is the preferred fluid for burn resuscitation per the Parkland formula due to its isotonic composition.
A patient with chronic kidney disease has a serum potassium of 6.2 mEq/L and peaked T-waves on ECG. What is the priority intervention?
Answer: Give IV calcium gluconate
IV calcium gluconate is the priority to stabilize cardiac membranes and prevent life-threatening dysrhythmias.
Which finding best indicates adequate fluid resuscitation in a critically ill patient?
Answer: MAP > 65 mmHg and urine output 0.5 mL/kg/hr
A MAP > 65 mmHg with urine output ≥ 0.5 mL/kg/hr reflects adequate organ perfusion and resuscitation.
A patient's serum sodium is 118 mEq/L and they are asymptomatic. What is the safest correction rate?
Answer: No more than 8-12 mEq/L in 24 hours
Correcting hyponatremia faster than 8-12 mEq/L per 24 hours risks osmotic demyelination syndrome.
Which electrolyte imbalance is most commonly associated with prolonged nasogastric suctioning?
Answer: Hypokalemic metabolic alkalosis
NG suctioning removes HCl and potassium, causing hypokalemia and metabolic alkalosis from hydrogen ion loss.
A patient on loop diuretics develops muscle cramps, fatigue, and a serum magnesium of 1.1 mEq/L. What electrolyte should also be checked?
Answer: Serum potassium
Hypomagnesemia frequently coexists with hypokalemia because magnesium deficiency impairs renal potassium conservation.